Arhitectura peisagera: Informatii, Critica si Idei.

Yazd – Adaptation lessons from a desert city

Yazd is my first desert city experience. I have contacted Mr. Hossein Amjad, an Iranian landscape architect, also member of the International Federation of Landscape Architects. In an introductory email I requested a meeting, specifying my interest in urban challenges such as drought, water supply and self-sustainability. Mr. Hossein has kindly offered an”educated tour” of Yazd together with his friend Mr . Mohammad Rahmani Moghadam, agronomical engineer. They have kindly guided me through the city, helping me understand how the city has been developed and how it develops today.

Maquette in the Museum of Water

Yazd is probably the only desert city were you will find a Museum of Water. The museum of water presents the techniques Yazd had developed, implemented and maintained hundreds of years to provide itself with sufficient water. The water was moderately used for domestic consumption, communal gardening and also the beautiful Persian gardens. The underground galleries – “quanat”, were dug from 3 to 10 meters underground and their well functioning was based on gravity and wind. The Qanat system has been developed about 1000 BC, that’s the decade when Latins came to Italy from the Danube Region, and later the Roman Empire was rising, Ancient Egypt was declining, Judaism, Hinduism, Buddhist and Zoroastrianism religions were being created. Persian architecture is fabulous, and the Zoroastian architecture particularly important as it has been the driver of physical and social development if the city, and also spiritual.

Yazd is considered to be the centre of Zoroastian culture. The Tower of Silence was a tomb-tower outside the city, but as the city kept on expanding, the building was not perceived as sacred monument anymore. The system became soon outdated after some thousands of years when the Iranian Zoroastrians preferred burial or cremation instead.

Wind catchers – cooling system in traditional Iranian architecture. The buildings in desert cities are different than buildings in different other geographical regions. They are provided with wind traps in their roofs to catch cooler breeze and direct it to the ground floor. The day/ night temperatures vary considerably from too cool to extreme high. The thick ceramic walls are high with ceilings that maximize the shade on the ground, and small windows are not placed on the south. The main function of the wind catchers are cooling ventilation within the building, but when the quanat crosses the underground, the ventilation will keep the water on a low temperature.

Yakhchāl – The ice house. Yazd is a city of old sophisticated carbon-neutral architecture. The ice house was supplied with ice brought from the mountains. When it was connected to a quanat system, in the winter time, the quanat water would be directed to supply the Yakhchāl with water. The water was freezing and stored in place up to 6 months a year. Some ice houses were big enough to store up to 5,000 m3 of ice. The walls of the Yakhchāl, called sārooj, are 2 meters thick and made of a water impenetrable mixture made of sand, clay, egg whites, lime, goat hair, and ash in specific proportions, and which was resistant to heat transfer.

The agriculture and urban agriculture. What was most impressive to me was that the water supply system was designed not only to supply water for domestic consumption but also for the local food production and irrigation of the beautiful Persian gardens inside the city. The water was not abundant, but was used wisely at the minimum required for the self sustainability of the villages the quanat system was serving.

Maize is used to control the soil and air humidity on ground.

I have also met a beautiful Persian woman, Samaneh, meteorogist at Atmospheric Sciences and Meteorological Research Center, managing a project called “Cloud seeding”, a Russian technology for artificial irrigation. The method, explained in the image below, is recently used for the agricultural production, and it contributes to the local production of food as well as export harvest.

Yazd is currently in a continuous expansion and the challenges of hosting more and more inhabitants increase the consumption of water, the food supply and climate change induced challenges. One example of issues that affect the city is drought and wind storms. The southern part of the county relies on the waters of Tigris and Euphrates rivers. According to the Middle East Monitor, in 2014 the Turkish government decided to stop the flow of the Euphrates river into Syria, affecting Iraq and indirectly Iran. With no water available, the communities depending on the river have suffered a lot. The weakened natural wind barriers or lack of wind blockages such as vegetation cover, led to heavy sand storms and continuous movement of hot air masses towards the Persian Gulf, and other sand storms deep into Iraq territory and further to Iran.

Yazd city has yet to solve the prospected issue of water supply and prepare itself for dealing with drought and irregular wind storms. Yazd is a great example of urban development adapted in all aspects over a long period of time, when the resources are properly managed and the city properly planned.

The water consumption continued to rise as more water consuming services and industries were developed in Yazd. In same time, the water availability was decreasing, from reasons related to climate change or human induced environmental threats and weaknesses. Today the quanat system is not functioning and the city buys its water from the neighbors. With plentiful supplies and innovations such as cloud seeding, is possible to ease the local issues, but maybe this is also what the Turkish government thought when they stopped the Euphrates in 2014. Not yet sure if the way to auto sustainability is reliance to technology, but is a step to tackle climate change and produce locally grown food, which is a highly prioritized issue.

Lessons learn: plan for moderation in consumption and avoidance of wastage, in particular when exploiting local natural resources. And permanent mindfulness (to include nature and people, not only systems, in particular when planning settlements).

I want to share with you a link to an inspiring story, of the water on Earth.